Jennifer Hudson's brother-in-law was charged with murder Tuesday in the shooting deaths of three of the actress's family members, including the 7-year-old son of his estranged wife.

William Balfour had been in custody since Oct. 24, when the bodies of Hudson's mother, Darnell Hudson Donerson, and brother, Jason Hudson, were discovered in their South Side home. The body of Julian King, Balfour's stepson and Hudson's nephew, was found in a sport utility vehicle three days later.

Until Balfour's arrest in the murder case Monday, police had publicly identified him only as a "person of interest" in the investigation. Balfour, 27, who previously was held on a parole violation, is charged with three counts of first-degree murder and one count of felony home invasion.

Balfour's attorney said his client is insistent about his innocence.

"It is scary as hell, he's charged with terrible crimes that he adamantly contends he's not guilty of," attorney Joshua Kutnick said before the announcement of the charges, which he said he expected.

Still, added Kutnick, "He's exhibited to me, at least, the patience to let the process unfold."

Chicago Police Superintendent Jody Weis said at a news conference Tuesday that although Balfour has not confessed to the crimes, he is "confident in the evidence." Investigators have not said what evidence they have linking Balfour to the killings, but said Tuesday that they are not looking for other suspects and believe Balfour acted alone.

"There is physical evidence," Deputy Superintendent Steve Peterson said, but he stopped short of saying whether that evidence linked Balfour to the crimes.

Weis praised the community for the way it "stepped up to the plate and helped police solve this case," but would not provide any details.

Police have said from the beginning that the slayings were domestic related, but they have not elaborated. They would not say, for example, if they believed the boy was part of any dispute between Balfour and his estranged wife, Hudson's older sister, Julia Hudson.

Police believe Julian was killed inside the SUV the same day as the adults, but "the exact timing" has not been determined, Peterson said.

Police have said far less than Illinois Prison Review Board Chairman Jorge Montes, who told reporters last month that Balfour's girlfriend or ex-girlfriend told police she saw Balfour with a gun "identical" to the weapon police recovered near the SUV where the boy's body was found - which they have said was the murder weapon.

When asked about the woman Tuesday, Peterson said that she cooperated with police, but would not say what information she provided, if any. Nor would he say that detectives have linked the weapon to Balfour.

Jennifer Hudson's publicist Lisa Kasteler declined to comment after Balfour's arrest on Monday, but Peterson said the family was "relieved and happy that the Chicago Police Department would bring this case to a successful conclusion."

Jennifer Hudson was a finalist in the 2004 season of "American Idol" and won her Oscar in 2007 for her film debut, a supporting role in "Dreamgirls." She has mostly stayed out of the spotlight and close to her family since the killings.

Detectives went to Stateville Correctional Center Monday afternoon, served an arrest warrant on Balfour and brought him back to Chicago.

Balfour had been in custody since the day the adults' bodies were discovered. After 48 hours - the longest Chicago police can hold a person without charges - he was taken by the Illinois Department of Corrections on a suspected parole violation. Balfour had served seven years for a 1999 attempted murder and vehicular hijacking conviction.

Balfour is scheduled to appear in bond court Wednesday afternoon. After the hearing, Cook County State's Attorney Anita Alvarez will talk about the case, her office said Tuesday.